21194639200 has 72 divisors (see below), whose sum is σ = 59133058992. Its totient is φ = 7266731520.

The previous prime is 21194639171. The next prime is 21194639203. The reversal of 21194639200 is 293649112.

It is a self number, because there is not a number n which added to its sum of digits gives 21194639200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21194639203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1886779 + ... + 1897978.

It is an arithmetic number, because the mean of its divisors is an integer number (821292486).

Almost surely, 2^21194639200 is an apocalyptic number.

21194639200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21194639200 is an abundant number, since it is smaller than the sum of its proper divisors (37938419792).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21194639200 is a wasteful number, since it uses less digits than its factorization.

21194639200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3784784 (or 3784771 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The spelling of 21194639200 in words is "twenty-one billion, one hundred ninety-four million, six hundred thirty-nine thousand, two hundred".